Water jet propulsion device



Nov. 5, 1968 R. B. GAMBLE 3,408,975

WATER JET PROPULSION DEVICE Original Filed June 9, 1966 INVENTOR.

D B. GAMBLE ATTORNEYS RI HAR BYW United States Patent 3,408,975 WATER JET PROPULSION DEVICE Richard B. Gamble, 7474 Lathers, Garden City, Mich. 48135 Continuation of application Ser. No. 556,359, June 9, 1966. This application Nov. 13, 1967, Ser. No. 682,668 8 Claims. (Cl. 115--12) ABSTRACT OF THE DISCLOSURE A water jet propulsion device is disclosed which has a housing structure simulating in miniature the appearance of the housing structure of a conventional outboard motor. The device has means by which it is pivotally mounted to a stern of a small boat to be manipulated in steering the craft, as is characteristic of an outboard motor. The interior of the housing structure is compartlnentized, and at least in part filled with buoyant material.

Said interior receives in an upright position a vertically elongated tube means, a sub-surface end of which projects beneath the structure and is equipped with a fitting affording a dual swivel-type connection to a low pressure water source, such as a garden hose. The upper end of the tube means is a jetting end in fixed location on the housing structure, which end discharges water aft-wise and downwardly toward a buoying surface. The jetting end is above that surface, so as to produce propulsion of the craft by jet-reaction alone, but the jet impinges the buoying surface in a manner to create a rooster tail effect.

This application is a continuation of application No. 556,539 filed June 9, 1966, and now abandoned.

The present invention relates to a water jet propulsion device, herein illustrated and described as being of miniature size, in which the boat propulsion is accomplished solely through the agency of above-water jet means, and in accordance with Newtons third law of motion, i.e., that to every action there is opposed an equal and opposite reaction. More particularly, the jet is a Water jet whose source is, in a miniature installation of the type referred to, an ordinary garden water hose pressurized at say, 30-40 pounds per square inch.

In general, it is an object of the invention to provide a Water jet propulsion device for propelling a boat operating strictly and solely upon the action-reaction principle from an above-water jet nozzle or orifice. That is, whatever force the water jet has in striking a pool or other water mass in which the boat is buoyed, is actually of insignificant or no effect in the propulsion of the craft.

Another object is to provide boat propulsion means of the sort referred to, in which a mount for the propulsion jet means also serves as a direction control or steering unit for the boat. Thus, in the illustrated embodiment of the invention, such mount may be in the form of a housing structure simulating in miniature a conventional outboard boat motor; with an arrangement fixedly mounted to the boat hull, as at the transom thereof, for pivotally mounting the motor structure to swing and steer the boat. As herein illustrated, such steering arrangement involves an operating arm projecting inboard of the boat and equipped with a pistol grip or the like for manipulation. In other embodiments of the invention, for example, in an inboard installation of the mount for the jet, other types of inboard-manipulated steering means may be resorted to.

Further in accordance with the invention, the relationship of the jet nozzle or orifice of the propulsion means, as mounted on the boat, is such that the Water hosepressurized jet is directed rearwardly and downwardly onto the surface of the buoying water in a way to produce a satisfying jet-simulating noise and rooster tail appearance effect, all of which contributes to the enjoyment of the craft in use.

Another object is to provide boat propulsion means of the character referred to, in which the jet-mounting, motorsimulating structure is readily and easily removable from one boat, for mounting on another.

In still further accordance with the invention, the improved structure is such that the speed of the boat may be determined readily and inexpensively by a selection of the cross sectional jetting area of its propulsion orifice, by the volume or pressure of water discharged, etc. For example, employing a garden hose pressure of 30 pounds per square inch, a miniature sized, plastic-constructed boat can be propelled at a rate of about six feet per second across a pound, pool or other buoying surface.

In a more specific aspect of the invention, a jetting tube terminating at its upper end in a restricted jet orifice or nozzle well above the surface, has a sub-surface connection to the garden hose through the agency of an improved coupling, by which a free relative swivel of the coupling and a hose connected thereto. Thus, steering changes, as produced by a swing of the jetting tube and its mount on a pivotal connection to the stern of the boat or other craft, do not result in undue drag to impede boat progress or undesirable kinking or curling of the sub-surface hose through which propulsive jet force is transmitted.

As indicated above, the propulsive Water jet is transmitter to the jet orifice at the upper end of a tube, preferably supported upright by and internally of a mounting or housing structure simulating an outboard motor (although other types of mount are of course contemplated). In one embodiment the orifice may be of rearwardly tapered cross-section variable in area by simply expanding the same manually. Another embodiment simply contemplates the flattening of the rear end of a circular-section jetting tube in order to produce the restriction at the orifice which converts fluid pressure to velocity. This alternative has the advantage of less cost and greater ease of production.

In general, it is an object of the invention to provide a boat having an improved jet propulsion device or unit, which unit, has means to readily and removably mount the same to the stern of the boat, including a pivotal connection enabling the unit to serve for steering as well as propulsion; and which unit, in basic distinction from other generally similar devices, discharges its water jet above the buoying surface and preferably at a rearward and downward angle to impinge said surface, thus enabling the production of the novel visual and sound jet effects mentioned above, both concurrently with the propulsion and steering of the boat.

The foregoing as well as other objects will become more apparent as this description proceeds, especially when considered in connection with the accompanying drawing illustrating the invention, wherein:

FIG. 1 is a side elevational view showing a typical installation of the water jet propelled structure of the invention upon the transom of a typically depicted, miniature size craft, indicating the reactive propulsion effect of the water jet, and the rooster tail-simulating action which it produces on the surface of the water on which the boat floats;

FIG. 2 is a fragmentary side elevational view, partially broken 'away'andin vertical section, through a typical mount for the propulsion device, shown as simulating an outboard motor, the view being sectioned on a front-torear center plane of the unit;

FIG. 3 is a fragmentary view in enlarged scale, and in vertical cross section, illustrating the improved doubleswiveling connection of an angled adapter or coupling to the jet tube of the unit, and of the coupling to the subsurface water hose;

FIG. 4 is a perspective view illustrating a water jet propulsion unit as produced in a somewhat different manner than in theembodiment of FIGS. 1 and 2, but with a generally similar propulsive and rooster tail-simulating action;

FIG. 5 is a fragmentary view in side elevation showing the modification in the jet orifice structure which results in the effect depicted in FIG. 4; and

FIG. 6 is a view in cross section through the jet orifice of FIGS, along line 66 of that figure.

Referring to FIGS. 1 and 2 of the drawing, a water jet propelling unit or device in accordance with one embodiment of the invention is generally designated by the reference numeral 10. FIG. 1 shows it as having a basically fixed but removable mount at 11 to the stern transom 12 of a boat 14 having the appearance of an outboard motor hull. As indicated above, the boat 14 and propulsion device or unit are miniaturized in size, in contemplation of being enjoyed on a pool, pond or other water surface of restricted area. Thus, the unit 10 has a mounting structure 15 simulating in appearance the housing or casing for the motor, shaft and propeller components of a conventional type of outboard motor; and the mount 11 which supports this housing-like mounting structure, preferably on the boat transom, is one which permits a free swing of unit 10 for the purpose of steering, as by means of the underwater rudder tail extension 16 of the structure 15.

Referring to FIG. 2, the latter includes an upper motor housing-simulating portion 18 and a depending portion 19, which terminates in the steering extension 16. It is contemplated that, in an embodiment like that of FIGS. 1 and 2 (also FIG. 4 to be described), the structure 15 may comprise a pair of simliar shells molded of a suitable plastic material, in the interest of low cost of production and lightness in weight, such molded halves being appropriately secured in light-tight relation to one another, as by bonding, along a central front-to-rear meeting plane.

By further preference, the interior of the housing structure is compartmentized, as by horizontal partitions 20 molded integral with its component halves; and the compartments defined by these partition elements may be filled with a suitable, very light weight foamy material 21, such as styrafoam. This insures buoyancy of the unit 10, in the event of a leak in the wall of its housing structure 15.

The pressurized jetting tube of the propulsion unit 10 is generally designated by the reference numeral 22. It is rigid and of vertically elongated cylindrical cross section, being received along the longitudnial center line of housing structure 15, for example in semi-circular recesses 23 formed in the partitions 20 at their respective meeting lines. The lower end of the tube 22 projects downwardly out of the housing structure extension 19 through a sealed opening 24, below which it is connected by an improved swivel coupling, generally designated 25, to the discharge end of an ordinary flexible garden hose 26, in a manner to be described.

As it projects upwardly beyond one of the partitions 20, the jetting tube 22 has a somewhat more than 90 curvilinear, rearward and downward bend at 28; and the tail extremity 29 of this portion is gradually reduced or constricted in a mildly tapereddiameter (FIG. 2) to afford a jetting orifice 30 of small cross sectional area.

For example, orifice 30 may be of as little as Aaf'dn diameter, although if desired and as indicated above, it can be manually enlarged readily using a simple awl, small drill bit or like tool. To this end the tube 22 may be of a non-metallic, semi-rigid character. It is unobstructed internally between its lower end and its opposite end orifice 30, inasmuch as its function is solely to transmit liquid propulsive force from hose 26 to and through orifice 30, wholly without resort to any force generating means withinthe tube.

Jetting of water through the gradually restricted, semicircular orifice 30, at a rearw'ardly' and downwardly inclined angle to the surface or level of, a body of water produces the effect indicated in FIG. 1, i.e., a rather concentrated jet or spurt S which, impinging the surface, produces a rearwardly and upwardly flaring rooster tail appearance atR, with accompanying'sound, adding to the enjoyment of the boat ride by the occupant. As indicated above, however, the primary boat-propelling action is due to the jet reactive principle; and the physical impingement of the spurt or stream S upon the water surface makes no contribution to propulsion.

The mounting means at 11, by which the propulsion unit or device 10 is supported on the stern transom 16 of the craft 14 may be of many different sorts, but all, preferably, having means enabling the unit 10 to be swung about a vertical axis for the steering of the boat. As typically shown in FIG. 2, the mount 11 comprises a horizontally disposed, U-shaped bracket 32 of steel or other rigid material, which bracket is welded or otherwise rigidly secured at 33 to the jetting tube 22, adjacent the rear-turned portion 28 of the latter. The arms of bracket 32 extend forwardly and outwardly through the portion 19 of the motor-simulating mounting structure 15, and the uppermost arm is forwardly elongated at 34 and provided with a grip 35 for manipulation by the boat occupant.

An upright pivot pin 36 extends between the arms of bracket 32, for the purpose of swiveling the latter to a clamping bracket 37, with nylon washers 38 interposed between this bracket and the respective arms of bracket 32. Bracket 37 carries a threaded clamping screw 39 adapted to be taken up against the boat transom 12 for a rigid connection of unit 10 to the boat, yet one permitting a considerable extent of arcuate swing of the latter for the purpose of steering.

FIGS. 4, 5 and 6 illustrate a propulsion unit 10 similar in all respects to that described in detail above, save for the fact that its jetting tube, specially designated 40 in FIGS. 5 and 6, has orifice means of a different sort. Thus, in this embodiment, the rearwardly and downwardly bent upper portion 41 of tube 40 is substantially flattened at a rear orifice extremity 42, preferably in a direction to leave the latter in a vertical plane.

Thus, there is produced, as best shown in FIG. 6, a jetting orifice 43 of very much restricted cross sectional area, for the purpose of adequately converting water pressure into velocity; and the effect of this variation in orifice shape is illustrated in FIG. 4. That is, the jet is in the form of a stream S which, in impinging the water surface, produces a rooster tail effect at R similar to that shown at R in FIG. 1. The advantage of the orifice provisions of FIGS. 5 and 6 resides in the fact that the shaping of the tube 40* is facilitated, as compared with the tapering embodiment of FIG. 2, involving as it does a simple flattening operation which can be quickly and easily performed using a vise.

FIG. 3 illustrates, in enlarged scale, structural features of the coupling 25 by which the lower, sub-surface end of jet tube 22 is operatively connected in a swiveled manner to the discharge end fitting 45 of the water hose 26, which fitting 45 is typically a male fitting clinched onto the end of tube 26 in the usual manner.

Coupling 25 is in the form of a mildly obliquely bent, rigid tube 46, it being intended that the bend of the latter shall be downwardly and axially to the rear when properly connected up to tube 22 (or 40) and hose 26. The upper end of tube 46 has a threaded male formation 47, which is threadedly engaged by an apertured type female fitting 48 telescoped on the bottom of tube 22 and adapted to downwardly engage an outward flange 49 of the latter. A relatively widely flanged washer 50 of a suitable plastic, such as nylon, is interposed between the upper male threaded end of coupling tube 46 and the flange 49 of jetting tube 22, thus effecting an adequate, near leakproof seal at this end of the union, while still enabling a relative swivel of coupling about the axis of tube 22.

At its lower end, the coupling tube 46 is enlarged in diameter at 52 to form a radially outwardly extending annular shoulder, beneath which an annular, internally threaded female coupling fitting 53 is slipped in telescoping engagement with member 46; the latter is then radially outwardly upset at 54 to retain fitting 5'3 axially in place, with a swiveled connection at 55 to coupling tube 46. Fitting 53 threadedly engages male hose fitting 45, with an annular nylon sealing gasket 56 interposed. Thus a union is provided at the lower end of coupling 25 which enables a free swivel of the water garden hose 26 relative to the coupling. The two swivel unions at the top and bottom of tube 46 permit the hose 26 to be trailed with minimal curling or snarling.

The invention affords a very inexpensively produced unit for the above-water propulsion of a water craft or like buoyant unit, which is of very light-weight construction, readily applied to and removed from the stern of the craft, as for storage. In combining, with its operational propulsive and storing effects, visual and audible elfects to amuse the user or watcher, the subject matter of the invention is considered a substantial improvement over previous units of the same general nature.

What is claimed is:

1. A water jet propulsion unit simulating in miniature an outboard motor in appearance, comprising a mounting structure so simulating such motor and having means to mount the same adjacent the stern of a boat or other buoyantly sustained craft, including means enabling a rotary swing of said structure as a whole about an upright pivotal axis adjacent said stern for the steering of the craft, and water pressurizable propulsion tube means mounted on and extending upwardly within said structure, said tube means including a sub-surface water intake end and a jetting end having a terminal jetting orifice fixed relative to said mounting structure and the tube means, said tube means being internally unobstructed between said intake and jetting ends, the upper end of the tube means being directed rearwardly to said orifice and being positioned by said mounting structure, when the latter is mounted for steering by said first named means on said craft, so that said orifice of the tube means is above the surface buoying the craft, with said jetting end and orifice extending aft of the craft and in a downward inclination to the buoying surface, the water jetting under pressure from said orifice and effecting a purely jet-type propulsion of the craft, accompanied by a substantial disturbance of the buoying surface by the water jet.

2. The propulsion unit of claim 1, in which said mounting structure is internally compartmentized for buoyancy.

3. A water jet propulsion unit of the type described, comprising a mounting structure having means to mount the same adjacent the stern of a boat or other buoyantly sustained craft, and water pressurizable propulsion tube means mounted on said structure, said tube means including a jetting end having a terminal jetting orifice, the tube means being positioned by said mounting structure, when the latter is mounted by said first named means on said craft, so that said orifice of the tube means is above the surface buoying the craft, with said jetting end extending aft of the craft, said mounting structure simulating an outboard motor structure in appearance and said tube means having a sub-surface end, and coupling means at said last named end to effect a double swivel connection of the tube means to a pressurizing hose, said structure receiving said tube means in an upright position in its interior with said sub-surface end of the tube means projecting downwardly out of the structure, said structure being internally compartmentized and at least in part filled with buoyant material.

4. A water jet or like propulsion unit of the type described, comprising a mounting structure having means to removably mount the same adjacent the stern of a boat or other buoyantly sustained craft at the aft end of the latter, said means having provision to enable a swing of said mounting structure about a substantially upright axis relative to the craft, whereby the structure may serve in the steering of the craft at a sub-surface part of the structure, and water pressurizable propulsion tube means mounted on said structure, said tube means including a jetting end having a terminal jetting orifice of restricted mouth size, the tube means being positioned by said mounting structure, when the latter is mounted by said first named means on said craft, so that said orifice of the tube means is above the surface buoying the craft, with said jetting end extending aft of the craft and at a downward inclination toward said surface, said mounting structure simulating an outboard motor structure and receiving said tube means in an upright position in its interior with said sub-surface end of the tube means projecting downwardly out of the structure, said structure being internally compartmentized and at least in part filled with buoyant material.

5. A water jet device for propelling a buoyant craft substantially solely through jet reactive power derived from a relatively low pressure source, comprising an upright jetting tube having at its upper end a rearwardly extending, above-surface orifice extremity and at its lower end a sub-surface connecting extremity, means to mount said jetting tube on said craft in such position that said orifice extremity will be above a surface buoying the craft and said connecting extremity below said surface, and coupling means to effect a swiveled connection of said lastnamed extremity to a water pressure hose source, said coupling means comprising a tubular member having provision at its opposite ends to afford individual swivel connections at those ends to the connecting extremity of said jetting tube and to said pressure hose source, respectively.

6. A water jet propulsion unit simulating in miniature an outboard motor in appearance, comprising a mounting structure so simulating such motor and having means to mount the same adjacent the stern of a boat or other buoyantly sustained craft, including means enabling a rotary swing of said structure as a whole about an upright pivotal axis adjacent said stern for the steering of the craft, water pressurizable propulsion tube means mounted on and extending upwardly within said structure, said tube means including a sub-surface water intake end and a jetting end having a terminal jetting orifice fixed relative to said mounting structure and the tube means, the upper end of the tube means being directed rearwardly to said orifice and being positioned by said mounting structure, when the latter is mounted for steering by said first named means on said craft, so that said orifice of the tube means is above the surface buoying the craft, with said jetting end and orifice extending aft of the craft and in a downward inclination to the buoying surface, the water jetting under pressure from said orifice and effecting a purely jet-type propulsion of the craft, accompanied by a substantial disturbance of the buoying surface by the water jet, and coupling means to effect a connection of said sub-surface end of the tube means to a pressurizing hose.

7. The propulsion unit of claim 6, in which said coupling connection is a double-acting swivel one, including a tubular member having means to swivel opposite ends thereof to said tube means and to the pressurizing hose, respectively.

3,408,975 8 8. The propulsion unit of claim 6, in which said mount- FOREIGN PATENTS ing structure is internally compartmentized for buoyancy, being at least in part filled with buoyant material. 7 4 6/1954' France References Cited 5 DUANE A. REGER, Primary Examiner. UNITED STATES PATENTS TRYGVE M. BLIX,- Assistant Examiner.

3,090,346 5/1963 Burgin. 

